This invention relates to radio communications, and more specifically to a radio frequency (RF) circuit reconfigurable between an RF mixer with fixed gain, RF mixer with variable gain, an RF amplifier with fixed gain, an RF amplifier with variable gain, and the ability to selectively switch, isolate and/or combine multiple RF signal paths together.
Radio frequency (RF) communications equipment generally employs a combination of mixers, amplifiers and switches to route signals through alternate paths for filtering or processing. Amplifiers are useful to increase the power level of a signal of interest. In RF transmission, RF mixers are used to transpose radio frequencies to a useful signal for transmission and delivery at an intermediate frequency. Conversely, in reception, mixers are used to transpose the RF frequency of a received signal to a relatively low intermediate frequency for processing by downstream electronic circuits. Switches are useful for selectively choosing different signal paths through a system cascade to allow flexibility in filtering, gain shaping, and/or processing of information as desired by the designer.